CN217453193U

CN217453193U - Machine tool comprising a rotary indexing device

Info

Publication number: CN217453193U
Application number: CN202221324891.2U
Authority: CN
Inventors: 原田芳树; 池田阳平
Original assignee: Komatsu NTC Ltd; Tsudakoma Industrial Co Ltd
Current assignee: Tsudakoma Corp; Komatsu NTC Ltd
Priority date: 2021-06-07
Filing date: 2022-05-27
Publication date: 2022-09-20
Anticipated expiration: 2032-05-27
Also published as: CN115502774A; US20220388104A1; TW202247939A; KR20220165191A; JP2022187057A; EP4101582A1

Abstract

The utility model relates to a staff can manage the lathe including rotatory indexing means of the oil mass in the storage of rotatory indexing means easily. The machine tool includes a rotary indexing device for indexing an angular position of a member to be rotated attached to an end portion of a rotary shaft, the rotary indexing device including a frame for housing the rotary shaft in a rotatably supported state, a drive motor for rotationally driving the rotary shaft, and a drive transmission mechanism housed in a space inside the frame and transmitting rotation of an output shaft of the drive motor to the rotary shaft, the drive transmission mechanism including a gear mechanism, the space including at least one storage portion for storing lubricating oil for lubricating at least the gear mechanism, the rotary indexing device including a detection device for detecting a height position of an oil surface of the lubricating oil stored in the storage portion, the detection device being provided in one-to-one correspondence with a detection target storage portion set as a detection target among the at least one storage portion.

Description

Machine tool comprising a rotary indexing device

Technical Field

The present invention relates to a machine tool including a rotary indexing device for indexing an angular position of a rotary object member attached to an end portion of a rotary shaft, wherein the rotary indexing device includes a frame for housing the rotary shaft in a rotatably supported state, a drive motor for rotationally driving the rotary shaft, and a drive transmission mechanism for housing a space inside the frame and transmitting rotation of an output shaft of the drive motor to the rotary shaft, the drive transmission mechanism includes a gear mechanism, and the space includes one or more storage portions for storing at least lubricating oil for lubricating the gear mechanism.

Background

As the machine tool including the rotary indexing device, there is a device described in patent document 1. The machine tool disclosed in patent document 1 includes an NC circular table (rotary indexing device) including a rotary table configured to be able to mount a workpiece. In the rotary indexing device, the frame is formed as a case having a space therein. A rotating shaft having a table attached to one end thereof is accommodated in the space of the frame (casing). A drive motor (servo motor) for rotationally driving the rotary shaft (rotary table) is attached to the frame. The drive motor and the rotary shaft are coupled via a drive transmission mechanism for transmitting the rotation of the drive motor to the rotary shaft, and the drive transmission mechanism is also housed in the space of the frame.

The drive transmission mechanism includes a gear mechanism such as a worm and a worm wheel. In addition, lubricating oil is stored in a portion of the space corresponding to the gear mechanism so as to lubricate the gear mechanism. In other words, the space includes a reservoir portion that stores lubricating oil for lubricating the gear mechanism.

In such a machine tool, the amount of lubricating oil (oil amount) in the reservoir portion of the rotary indexing device may vary. Specifically, in the reservoir portion, the oil amount may decrease due to leakage or the like, or the oil amount may increase due to intrusion of the coolant. When the amount of oil is reduced, the gear mechanism is in an insufficiently lubricated state. When the amount of oil increases, the lubricating oil is in a state in which the lubricating performance thereof is degraded by the mixing of the coolant that has entered the reservoir portion. In either case, the gear mechanism wears out with the operation, and the accuracy of the angular position of the workpiece indexed by the rotary indexing device is reduced.

Therefore, in such a machine tool, the worker needs to manage the amount of oil. Therefore, a general rotary indexing device includes a direct-view type oil gauge as a structure for managing the oil amount, and the direct-view type oil gauge is provided so that a worker can visually recognize the height position of the oil level in the storage section. It is needless to say that the oil amount meter is provided at a position corresponding to the reservoir of the frame so as to be visible from the outside.

Prior patent literature

Patent document

Patent document 1: japanese patent laid-open No. 2020 and 44614

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

However, in a conventional machine tool including a rotary indexing device, the rotary indexing device is provided in a machining area of the machine tool in which a workpiece is machined. Therefore, in many cases, the rotary indexing device has dirt adhered to the surface thereof due to coolant and chips scattered to the machining area in association with the machining of the workpiece.

In this case, when the structure for managing (confirming) the oil amount is the oil amount meter provided as described above, the oil amount (height position of the oil surface) may not be confirmed in the original state due to the dirt adhering to the surface of the rotary indexing device as described above. In addition, when the oil amount cannot be checked due to dirt, the worker needs to perform a cleaning operation for removing the dirt adhering to the periphery of the oil amount meter in order to check the oil amount.

In this way, the conventional machine tool including the rotary indexing device has a problem that the amount of oil is managed by checking the amount of oil by the oil gauge which may be accompanied by the cleaning operation, and a large burden may be imposed on a worker in the management.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a machine tool including a rotary indexing device that can reduce a burden imposed on a worker in managing the amount of oil in the storage unit.

Means for solving the problems

The utility model discloses a lathe including being used for carrying out the rotatory indexing means's that divides in the angular position of the rotatory object part that will install in the tip of rotation axis, especially use following lathe as the prerequisite: the rotary indexing device includes a frame that houses the rotary shaft in a rotatably supported state, a drive motor that rotationally drives the rotary shaft, and a drive transmission mechanism that is housed in a space inside the frame and transmits rotation of an output shaft of the drive motor to the rotary shaft, wherein the drive transmission mechanism includes a gear mechanism, and the space includes one or more storage portions that store lubricating oil that lubricates at least the gear mechanism.

In addition, the present invention is characterized by including a detection device for detecting a height position of an oil surface of the lubricating oil stored in the storage portion, wherein the detection device is provided in one-to-one correspondence with a detection target storage portion set as a detection target in one or more of the storage portions.

In addition, the machine tool of the present invention may further include a display device connected to the detection device and displaying information on the height position detected by the detection device.

Further, the display device may be provided outside a cover covering a machining area where the rotary indexing device is disposed to machine the workpiece.

The concrete scheme of the utility model is as follows respectively.

A machine tool according to the present invention is a machine tool including a rotary indexing device for indexing an angular position of a member to be rotated attached to an end portion of a rotating shaft, the rotary indexing device including a frame that houses the rotating shaft in a rotatably supported state, a drive motor that rotationally drives the rotating shaft, and a drive transmission mechanism that is housed in a space inside the frame and transmits rotation of an output shaft of the drive motor to the rotating shaft, the drive transmission mechanism including a gear mechanism, the space including one or more storage portions that store at least lubricating oil that lubricates the gear mechanism, the machine tool being characterized in that the drive transmission mechanism includes a gear mechanism,

comprises a detection device for detecting the height position of the oil surface of the lubricating oil stored in the storage part,

the detection device is provided in one-to-one correspondence with a detection target storage unit set as a detection target among the one or more storage units.

A second aspect is a machine tool including a rotary indexing device based on the first aspect, including a display device connected to the detection device and displaying information related to the height position detected by the detection device.

A third aspect is a machine tool including a rotary indexing device based on the second aspect, characterized in that,

the display device is provided outside a cover that covers a machining area where the rotary indexing device is disposed and the workpiece is machined.

The utility model has the following effects.

According to the present invention, in the machine tool including the rotary indexing device as the above-described premise, the detection device for detecting the height position of the oil level in the detection target storage portion is provided in a one-to-one manner with respect to the detection target storage portion in the rotary indexing device. In this way, by setting the reservoir portion requiring the management of the oil amount as the detection target reservoir portion, the oil amount in the detection target reservoir portion can be managed using the detection result regarding the height position of the oil surface of the detection device. Therefore, according to the present invention, as described above, compared to the conventional machine tool including the rotary indexing device that manages the amount of oil using the oil amount meter, the burden on the worker for performing the cleaning operation can be eliminated, and the burden on the worker in managing the amount of oil can be reduced.

Further, the present invention provides a machine tool including a display device for displaying information relating to the height position of the oil level detected by the detection device, wherein the information displayed by the display device can be visually confirmed by an operator, and the operator can grasp the information relating to the height position of the oil level. In this way, the operator can manage the amount of oil while grasping the state of the amount of oil, and thus can manage the amount of oil more appropriately.

Further, in the machine tool of the present invention, the display device is provided outside a cover covering a machining area where the rotary indexing device is disposed and the workpiece is machined, and the display device can be visually confirmed outside the cover. Therefore, it is possible to more easily confirm (display) the information on the oil amount for managing the oil amount.

Drawings

Fig. 1 is a front view showing one embodiment of a machine tool to which the present invention is applied.

Fig. 2 is a front view illustrating an inclined circular table in the machine tool of fig. 1.

Fig. 3 shows a left side view of the tilted circular table of fig. 1, partially as a cross-sectional view along line a-a of fig. 2.

Fig. 4 shows a front view of the tilted circular table of fig. 1, largely as a cross-sectional view taken along line B-B of fig. 3.

FIG. 5 is a top view, partially in section, of an inclined circular table.

Fig. 6 is a sectional view showing a state of cutting the inclined circular table in a horizontal direction.

Description of the symbols

1-machine tool, 1 a-spindle, 1 b-machine base, 1 c-column, 1 d-spindle head, 1 e-table, 1 f-outer cover (cover), 1 h-peripheral wall, 2-inclined circular table (rotary index device), 3-inclined drive section (rotary index device), 4-rotary drive section (rotary index device), 5-base frame, 5 a-stand, 5 b-support table (drive support table), 5 c-support table (driven support table), 6-inclined frame (rotary object part), 7-rotary table (rotary object part), 8-rotary shaft (inclined drive shaft), 9-rotary shaft (driven shaft), 9 a-shaft, 9 b-wall, 9 c-through hole, 14-inclined table, 14 a-support shaft housing hole, 14 b-rotary shaft housing hole, 14 c-inclined table side space, 14d a large diameter portion for worm, 14e a front side surface, 14f a front wall, 14h a through hole, 14i a through hole, 15 an arm portion (arm portion on the side of tilting drive shaft), 16 an arm portion (arm portion on the side of driven shaft), 16a space for gear train, 16b a through hole, 16c a through hole, 16d a front side surface, 16e a front wall, 16h a through hole, 16i a through hole, 17 a support shaft, 19a back cover, 19a through hole, 21a tilting drive motor, 21a output shaft, 22a frame body portion, 22a receiving hole for tilting shaft, 22b a receiving hole for worm shaft, 22c a large diameter portion, 22d an outer side surface, 22e a frame side communication passage (first frame side communication passage), 22f a frame side communication passage (second frame side communication passage), 22h a side wall, 22i a through hole, 22j a through hole, 22 r-front side face, 22 s-lower space, 23-motor mounting portion, 23 a-inner space, 23 b-wall portion, 23 c-through hole, 23 d-outer side face, 24-back cover, 24 a-through hole, 25-oil seal, 26-worm gear mechanism (gear mechanism), 26 a-worm wheel, 26 b-worm, 26 c-worm shaft, 27-gear train, 27 a-drive gear, 27 b-drive gear, 27 c-driven gear, 28-drive transmission mechanism, 29-cover member, 31-storage portion (first storage portion), 31 a-main body portion side space, 32-storage portion (second storage portion), 33-storage portion (third storage portion), 34-storage portion (fourth storage portion), 35-oil seal, 36-O-ring, 37-first seal member, 38-second seal member, 39-oil seal, 41-rotary drive motor (drive motor), 41 a-output shaft, 43-drive transmission mechanism, 44-worm gear mechanism (gear mechanism), 44 a-worm wheel, 44 b-worm, 44 c-rotary drive shaft, 45-gear train, 45 a-drive gear, 45 b-drive gear, 45 c-driven gear, 51-oil seal, 52-oil seal, 53-O-ring, 54-third seal member (oil seal), 55-oil seal, 56-O-ring, 57-fourth seal member (oil seal), 61-detection device (first detection device), 61 a-main body seat, 61 b-attachment surface, 61 c-detection hole, 61 d-detector-side communication passage (first detector-side communication passage), 61 e-detector-side communication passage (second detector-side communication passage), 61 h-detector, 61 i-detector main body, 61 j-detection rod, 61 p-O-ring, 61 q-O-ring, 62-detection means (second detection means), 62 a-main body seat, 62 b-attachment surface, 62 c-detection hole, 62 d-detector side communication path (first detector side communication path), 62 e-detector side communication path (second detector side communication path), 62 h-detector, 62 i-detector main body, 62 j-detection rod, 62 p-O-ring, 62 q-O-ring, 63-detection means (third detection means), 63 a-main body seat, 63 b-attachment surface, 63 c-detection hole, 63 d-detector side communication path (first detector side communication path), 63 e-detector side communication path (second detector side communication path), 63 h-detector, 63 i-detector main body, 63 j-detection rod, 63 p-O-ring, 64-detection means (fourth detection means), 64 a-main body seat, 64B-mounting surface, 64 c-detection hole, 64 d-detector-side communication path (first detector-side communication path), 64 e-detector-side communication path (second detector-side communication path), 64 h-detector, 64 i-detector body, 64 j-detection rod, 64 p-O-ring, 71-display device, 71 a-display unit, 72-display device, 72 a-display unit, 73-display device, 73 a-display unit, 74-display device, 74 a-display unit, L1-axis, L1' -axis, L2-axis, L3-axis, L4-axis, B1-bearing, B2-bearing, B3-bearing, B4-bearing, B5-bearing, B6-bearing, B7-bearing.

Detailed Description

An embodiment (example) of a machine tool 1 to which the present invention is applied will be described below with reference to fig. 1 to 6. As shown in fig. 1, the machine tool 1 of the present embodiment is a machine tool 1 in which the direction of the rotation axis of the spindle 1a is parallel to the horizontal direction (so-called horizontal machining center). The machine tool 1 includes a bed 1b serving as a base, a column 1c supported movably in a horizontal direction (X-axis direction) with respect to the bed 1b, a spindle head 1d supported movably in a vertical direction (Y-axis direction) with respect to the column 1c, and a table 1e provided on the bed 1b movably in a direction (Z-axis direction) orthogonal to the X-axis direction and the Y-axis direction. The machine tool 1 of the present embodiment is provided with a box-shaped exterior cover 1 f. The exterior cover 1f is attached to the machine base 1b so as to cover an area above the machine base 1b including a machining area of the machine tool 1 in which a workpiece is machined.

The machine tool 1 is provided with an inclined circular table 2 for indexing the angular position of the workpiece. More specifically, as shown in fig. 2, the machine tool 1 of the present embodiment includes an inclined circular table 2 including two types of

rotary indexing devices

3 and 4, that is, an inclined driving unit 3 (rotary indexing device) for indexing the angular position of the rotary table 7 on which a workpiece is placed about an axis L1 in the horizontal direction, and a rotary driving unit 4 (rotary indexing device) for indexing the angular position of the rotary table 7 on which the workpiece is placed about an axis L2 of a support shaft 17 supporting the rotary table 7.

The inclined circular table 2 is mounted on a table 1e of the machine tool 1. The tilted circular table 2 includes a base frame 5 mounted on a table 1e of the machine tool 1, a tilt frame 6 supported by the base frame 5, and a rotary table 7 provided on the tilt frame 6 and on which a workpiece is mounted. The base frame 5 and the tilt frame 6 are frames in the tilt circular table 2 of the present embodiment including two kinds of rotary indexing devices, i.e., the tilt driving unit 3 and the rotary indexing unit 4, and correspond to the frame of the present invention.

The base frame 5 includes a plate-like base 5a serving as a base, and a pair of driving support base 5b and a driven support base 5c, which are support bases erected on the base 5a so as to be separated from each other in the longitudinal direction of the base 5 a. As shown in fig. 4 and 5, the base frame 5 has a pair of support bases rotatably supporting the tilt drive shaft 8 and the driven shaft 9 as the rotation shafts via bearings B1 and B2.

As shown in fig. 2, the tilt frame 6 is a so-called cradle-type support frame, and is composed of a tilt table 14 on which the swivel table 7 is provided, and a pair of arm portions for supporting the tilt table 14, i.e., a tilt drive shaft side arm portion 15 and a driven shaft side arm portion 16.

As shown in fig. 4 and 5, the tilt table 14 is plate-shaped in appearance, rectangular in shape when viewed in the plate thickness direction, and formed in a box shape having a space inside. The tilt frame 6 is fixed to the tilt drive shaft 8 and the driven shaft 9 corresponding to each arm between a pair of support bases (between the tilt drive shaft 8 and the driven shaft 9 as a pair of rotation axes) in the base frame 5, whereby the tilt frame 6 is supported to the base frame 5 via the pair of rotation axes.

Further, the tilt table 14 of the tilt frame 6 is provided with a support shaft 17 in a direction in which the direction of the axis L2 coincides with the plate thickness direction of the tilt table 14. More specifically, a housing hole (hereinafter, also referred to as a "housing hole for a support shaft") 14a for housing the support shaft 17 is formed in the tilt table 14 at a central portion thereof. The support shaft receiving hole 14a receives the support shaft 17 in a direction such that the direction of the axis line L2 coincides with the plate thickness direction. The support shaft 17 is rotatably supported via a bearing B3 with respect to the tilt table 14 in a configuration in which one end portion thereof protrudes from the upper surface of the tilt table 14 in the plate thickness direction.

A disc-shaped back cover 19 is provided in the support shaft receiving hole 14a on the opposite side to the side where the support shaft 17 protrudes in the plate thickness direction. A through hole 19a is formed in the back cover 19 at substantially the center of the disk shape. The through hole 19a is a hole having an inner diameter larger than the outer diameter of the other end portion of the support shaft 17. The rear cover 19 is attached to the tilt table 14 such that the other end of the support shaft 17 is fitted into the through hole 19 a.

A rotary table 7 is attached to the support shaft 17 at one end thereof. The rotary table 7 is a disk-shaped member, and is provided in a state where the center thereof coincides with the axis L2 of the support shaft 17. By being attached to the support shaft 17 in this manner, the rotary table 7 is supported to be rotatable with respect to the tilt table 14.

On this basis, as shown in fig. 2, the tilt circular table 2 includes a tilt driving section 3 for swing-driving the tilt frame 6 and a rotation driving section 4 for rotation-driving the rotation table 7.

The tilt driving unit 3 is provided in one support table (hereinafter also referred to as a "driving support table") 5b of the pair of support tables of the base frame 5, so as to rotationally drive a rotary shaft (hereinafter also referred to as a "tilt driving shaft") 8 rotatably supported in the driving support table 5 b. Therefore, the tilt driving unit 3 includes a tilt driving motor 21 as a driving source for rotationally driving the tilt driving shaft 8. The tilt drive motor 21 of the present embodiment corresponds to the drive motor of the present invention.

The tilt drive shaft 8 rotationally driven by the tilt drive motor 21 supports the tilt frame 6 indexed in angular position by the tilt drive unit 3. Therefore, the tilt drive shaft 8 and the drive support base 5b, which supports the tilt drive shaft 8 with the tilt drive motor 21 attached, also form part of the tilt drive unit 3. Further, in the tilt driving unit 3, the tilt frame 6 attached to the tilt driving shaft 8 and indexing the angular position around the axis L1 of the tilt driving shaft 8 corresponds to the rotation target member 6 in the rotary indexing device 3.

As shown in fig. 3 and 4, the tilt driving unit 3 is configured such that the driving support base 5b is composed of a frame main body 22 and a motor mounting portion 23, wherein the frame main body 22 is a portion that supports the tilt driving shaft 8 in a rotatable manner and is a main body, and the motor mounting portion 23 is a portion to which the tilt driving motor 21 as a driving source is mounted.

More specifically, the frame main body portion 22 of the drive support base 5b is substantially rectangular in appearance. The tilt drive shaft 8 is provided on the frame main body 22 so as to extend along both side surfaces in the thickness direction (X-axis direction) of the frame main body 22. Therefore, the frame body portion 22 has a housing hole (hereinafter also referred to as "tilt axis housing hole") 22a formed to penetrate in the thickness direction, and serves as a space for housing the tilt drive shaft 8. The tilt drive shaft 8 is supported by the frame main body 22 via a bearing B1 in such a manner that one end thereof slightly protrudes from the frame main body 22.

A disc-shaped rear cover 24 is provided in the tilt shaft receiving hole 22a on the opposite side to the side in the thickness direction from which the tilt drive shaft 8 protrudes. A through hole 24a is formed in the rear cover 24 at substantially the center of the disk shape. The through hole 24a is a hole having an inner diameter larger than an outer diameter of the other end portion of the inclined drive shaft 8. The rear cover 24 is attached to the frame main body 22 so that the other end of the tilt driving shaft 8 is fitted into the through hole 24 a.

As shown in fig. 3, the motor mounting portion 23 is similarly formed in a substantially rectangular parallelepiped shape in appearance, and is formed integrally with the frame main body portion 22 so as to protrude from a front side surface 22r of front and rear surfaces (substantially orthogonal to the two side surfaces) of the frame main body portion 22 in parallel with the thickness direction. The motor mounting portion 23 is formed in a box shape having a space (hereinafter also referred to as "internal space") 23a therein. However, the height of the motor mounting portion 23 is smaller than the height of the frame body portion 22, and is about 1/4 in the illustrated example.

In addition, the tilt drive motor 21 is attached to the upper surface of the motor attachment portion 23 with its output shaft 21a facing downward. Therefore, the tilt drive motor 21 is attached to the motor attachment portion 23 in this manner, and the tip of the output shaft 21a enters the internal space 23 a. Therefore, a through hole 23c through which the output shaft 21a passes is formed in the upper wall portion 23b including the upper surface of the motor mounting portion 23.

The tilt driving unit 3 includes a worm gear mechanism 26 coupled to the tilt driving shaft 8 and a gear train 27, and the gear train 27 includes a transmission gear 27b for transmitting the rotation of the output shaft 21a of the tilt driving motor 21 to the worm gear mechanism 26. That is, the tilt driving unit 3 is configured such that a drive transmission mechanism 28 for transmitting the rotation of the output shaft 21a of the tilt driving motor 21 as a driving source to the tilt driving shaft 8 is configured by two gear mechanisms of the worm gear mechanism 26 and the gear train 27.

The worm gear mechanism 26 includes a worm wheel 26a attached to the tilt drive shaft 8 and a worm shaft 26c having a worm 26b coupled to the worm wheel 26 a.

The worm wheel 26a is attached to the tilt drive shaft 8 as described above, and is therefore accommodated in the tilt-axis accommodation hole 22 a.

In the illustrated example, the worm shaft 26c is provided so that the axis L3 thereof is oriented in the vertical direction of the frame main body 22, and extends from a position above the worm wheel 26a to a position of the motor mounting portion 23 in the vertical direction.

Therefore, a hole (hereinafter, also referred to as a "worm-shaft housing hole 22 b") is formed in the frame body portion 22 to house the worm shaft 26c thus provided. The worm shaft storage hole 22b is formed to communicate with the inclined shaft storage hole 22a that stores the worm wheel 26 a. The worm shaft accommodating hole 22b is also formed in the frame body 22 so as to communicate with the internal space 23a of the motor mounting portion 23. The worm shaft accommodating hole 22b is formed as a hole that opens on the upper surface of the frame body portion 22 so that the worm shaft 26c can be inserted from the outside of the frame body portion 22. In addition, a disk-shaped lid member 29 is provided in the portion of the worm shaft storage hole 22b that opens at the upper surface of the frame body 22 so as to fit into the inner peripheral surface of the hole.

The worm shaft 26c includes the worm 26b at an intermediate position in the direction of the axis L3. The worm shaft 26c is supported by the frame body 22 via bearings B4 and B5 provided on both sides of the worm 26B in the vertical direction, respectively, in the worm shaft housing hole 22B so that the worm 26B meshes with the worm wheel 26a in the vertical direction.

In addition, the worm shaft 26c is coupled to the output shaft 21a of the tilt drive motor 21 via a gear train 27. More specifically, the drive gear 27a is fixed to the output shaft 21a of the tilt drive motor 21 attached to the drive support base 5b (motor attachment portion 23) and located in the internal space 23 a. On the other hand, the driven gear 27c is fixed to the lower end portion of the worm shaft 26c provided in the frame body 22 as described above. The driven gear 27c and the driving gear 27a are coupled to each other via one or more transmission gears 27b in the internal space 23 a.

The driven gear 27c is attached to the worm shaft 26c as described above, and is thus accommodated in the worm shaft accommodation hole 22 b. The rotation of the output shaft 21a of the tilt drive motor 21 is transmitted to the worm gear mechanism 26 through a gear train 27 including the drive gear 27a, the transmission gear 27b, and the driven gear 27 c.

In this way, the tilt driving unit 3 is configured to transmit the rotation of the output shaft 21a of the tilt driving motor 21 as a driving source to the tilt driving shaft 8 by the drive transmission mechanism 28 including the gear train 27 and the worm gear mechanism 26, and to rotate and drive the tilt driving shaft 8. Thereby, the tilt driving unit 3 drives the tilt frame 6 supported by the tilt driving shaft 8 to swing.

In the tilt driving unit 3, a first reservoir 31 and a second reservoir 32 are provided in a space inside the drive support base 5b, which space corresponds to each gear mechanism and is used for storing lubricating oil for lubricating the corresponding gear mechanism. The reservoir 31 corresponding to the worm gear mechanism 26 is provided in a space (hereinafter, also referred to as "main body side space") 31a formed by the inclined shaft accommodating hole 22a and the worm shaft accommodating hole 22 b.

More specifically, as shown in fig. 4, an oil seal 35 is provided in the tilt shaft accommodating hole 22a on the side from which the tilt drive shaft 8 projects, so as to be interposed between the inner peripheral surface of the tilt shaft accommodating hole 22a and the outer peripheral surface of the tilt drive shaft 8. Further, an oil seal 25 is provided in the tilt shaft housing hole 22a on the side where the back cover 24 is provided, so as to be interposed between the inner peripheral surface of the through hole 24a in the back cover 24 and the outer peripheral surface of the tilt drive shaft 8. Therefore, the tilt shaft accommodating hole 22a is in a state in which portions communicating with the outside of the frame main body portion 22 are sealed on both sides in the direction of the axis L1 of the tilt drive shaft 8.

As shown in fig. 3, an O-ring 36 is provided in the worm shaft storage hole 22b in the main body portion side space 31a, on the upper side in the direction of the axis line L3 of the worm shaft 26c, so as to be interposed between the outer peripheral surface of the cover member 29 and the inner peripheral surface of the worm shaft storage hole 22 b. Therefore, the worm shaft accommodating hole 22b is in a sealed state in which the upper side in the direction of the axis L3 of the worm shaft 26c communicates with the outside of the frame main body portion 22.

Thus, the body portion side space 31a formed by the inclined shaft accommodating hole 22a and the worm shaft accommodating hole 22b is in a sealed state at each portion communicating with the outside. In addition, in the body portion side space 31a, a first seal member 37 serving as an oil seal is provided so as to be interposed between the inner peripheral surface of the worm shaft accommodating hole 22B and the outer peripheral surface of the worm shaft 26c at a position below the lower bearing B4 of the worm shaft accommodating hole 22B supporting the upper and lower bearings 26B and the lower bearing B5 of the bearing B5. Thus, the portion of the body section side space 31a above the first seal member 37 is separated from the space below the first seal member 37 in the worm shaft storage hole 22 b.

In the upper portion of the main body side space 31a, lubricating oil for lubricating the worm gear mechanism 26 is stored. Therefore, the upper portion serves as a reservoir (first reservoir) 31 corresponding to the worm gear mechanism 26.

The gear train 27 connects the output shaft 21a of the tilt drive motor 21 and the worm shaft 26c, and the storage section 32 corresponding to the gear train 27 is provided in a space formed by the internal space 23a in the motor mounting section 23 and the portion of the worm shaft accommodating hole 22b communicating with the internal space 23 a.

More specifically, a second seal member 38 is provided as an oil seal so as to be interposed between the inner peripheral surface of the worm shaft housing hole 22b and the outer peripheral surface of the worm shaft 26c in the worm shaft housing hole 22b and below the position where the first seal member 37 is provided. Therefore, the worm shaft accommodating hole 22b is also configured to be separated from the space (lower space) 22s below the second seal member 38 and the space above the second seal member 38 by the second seal member 38.

The driven gear 27c is attached to the worm shaft 26c at an end portion located below the position where the second seal member 38 is provided. An oil seal 39 is provided in the motor mounting portion 23 so as to be interposed between the inner peripheral surface of a through hole 23c through which the output shaft 21a of the tilt drive motor 21 passes and the outer peripheral surface of the output shaft 21 a. Therefore, the inner space 23a of the motor mounting portion 23 is sealed at a portion communicating with the outside.

The internal space 23a of the motor mounting portion 23 and the lower space 22s of the worm shaft accommodating hole 22b communicate with each other as described above to form a space in which the gear train 27 is accommodated, and the space in which the gear train 27 is accommodated is sealed by the oil seal 39 around the output shaft 21a and the second sealing member 38. In addition, lubricating oil for lubricating the gear train 27 is stored in a space for housing the gear train 27. Therefore, this space serves as a reservoir (second reservoir) 32 corresponding to the gear train 27.

As shown in fig. 2 and 5, the rotation driving unit 4 is configured to rotatably drive the support shaft 17 supported by the tilt table 14 and the rotation table 7 attached to the support shaft 17. Therefore, the rotation driving unit 4 includes a rotation driving motor 41 as a driving source for rotationally driving the support shaft 17. The rotary drive motor 41 of the present embodiment corresponds to the drive motor of the present invention.

In the present embodiment, the rotary drive motor 41 is provided so as to be supported by the other support base (hereinafter also referred to as "driven support base") 5c of the pair of support bases of the base frame 5. However, in the tilt circular table 2, since the support shaft 17 rotationally driven by the rotational drive motor 41 is supported by the tilt frame 6 (tilt table 14) which is driven to swing as described above, the rotational drive motor 41 is provided in a form of being attached to a rotational shaft (hereinafter also referred to as a "driven shaft") 9 which is rotatably supported with respect to the driven support base 5 c. That is, the rotary drive motor 41 is supported by the driven support base 5c via the driven shaft 9. Therefore, the driven support base 5c and the driven shaft 9 also form a part of the rotation driving unit 4.

Also, the support shaft 17 driven by the rotary drive motor 41 is rotatably supported in the tilt table 14 in the tilt frame 6, and is coupled with the rotary drive motor 41 by a drive transmission mechanism 43 provided inside the tilt frame 6 as described later. Therefore, the support shaft 17 and the tilt frame 6 also form a part of the rotation driving unit 4. Further, in the rotary drive unit 4, the rotary table 7 attached to the support shaft 17 and indexed in angular position about the axis L2 of the support shaft 17 corresponds to the rotary target member 7 in the rotary indexing device 4.

As shown in fig. 5 and 6, the rotation driving unit 4 has the following structure for the driven shaft 9: a shaft portion 9a formed in a hollow cylindrical shape and a wall portion 9b provided at one end side of the shaft portion 9a are integrally formed. However, the wall portion 9b is formed to close the shaft portion 9a at one end side of the shaft portion 9 a. The hollow cylindrical shaft portion 9a has an inner diameter large enough to accommodate the rotary drive motor 41. A through hole 9c having a size capable of inserting the output shaft 41a of the rotation drive motor 41 is formed in the wall portion 9b and substantially in the center of the wall portion 9 b. The driven shaft 9 is supported by the driven support base 5c via a bearing B2 at a position where the one end side thereof in the direction of the axis L1 'is located in the direction of the tilt drive shaft 8 and the axial center thereof coincides with the axial center of the tilt drive shaft 8 when viewed in the direction of the axis L1'.

In addition, a part of the rotation driving motor 41 is housed in the shaft portion 9a of the driven shaft 9, and is attached to the driven shaft 9 with its output shaft 41a facing in a direction of inclining the driving shaft 8 side. In this attached state, the output shaft 41a of the rotary drive motor 41 is inserted into the through hole 9c in the wall portion 9b of the driven shaft 9 and protrudes from the driven shaft 9 (wall portion 9b) toward the inclined drive shaft 8.

The rotation driving unit 4 includes a worm gear mechanism 44 coupled to the support shaft 17, and a gear train 45 including a transmission gear 45b for transmitting the rotation of the output shaft 41a of the rotation driving motor 41 to the worm gear mechanism 44. That is, the rotation driving unit 4 is configured such that the drive transmission mechanism 43 for transmitting the rotation of the output shaft 41a of the rotation driving motor 41 as the driving source to the support shaft 17 is constituted by two gear mechanisms of the worm gear mechanism 44 and the gear train 45.

The worm gear mechanism 44 includes a worm wheel 44a attached to the support shaft 17 and a rotary drive shaft 44c having a worm 44b coupled to the worm wheel 44 a.

As shown in fig. 4, the worm wheel 44a is attached to the support shaft 17 as described above, and is thus accommodated in the support shaft accommodating hole 14 a. As shown in fig. 5 and 6, the drive shaft 44c is rotated such that the axis L4 thereof is oriented in a direction parallel to the axis L1' of the driven shaft 9, and is disposed in the tilt table 14 of the tilt frame 6 in such a manner that the worm 44b meshes with the worm wheel 44 a.

Therefore, a hole (a receiving hole for a rotation shaft) 14b for receiving the rotation driving shaft 44c provided in this manner is formed in the tilt table 14, and the receiving hole for a rotation shaft 14b communicates with the receiving hole for a support shaft 14a for receiving the worm wheel 44 a. The rotation drive shaft 44c is supported by the tilt table 14 through bearings B6 and B7 provided on both sides of the worm 44B in the direction of the axis L4 thereof in the rotation shaft accommodating hole 14B. In addition, the rotary drive shaft 44c is coupled to the output shaft 41a of the rotary drive motor 41 via a gear train 45.

More specifically, the rotation shaft accommodating holes 14b for accommodating the rotation drive shaft 44c are formed so as to open on both sides of the rotation drive shaft 44c in the direction of the axis L4 on the side surface of the tilt table 14. The two side surfaces of the tilt table 14 are the side surfaces to which the pair of arm portions of the tilt frame 6 are attached, respectively. Therefore, one end side of the rotation drive shaft 44c in the direction of the axis L4 is the inclined drive shaft 8 side, and the other end side is the driven shaft 9 side. The rotation shaft receiving hole 14b is closed by an arm portion 15 on the tilt drive shaft side on the tilt drive shaft 8 side.

On the other hand, a space (gear train space 16a) extending from the rotation shaft receiving hole 14b of the tilt table 14 to the through hole 9c of the driven shaft 9 is formed in the arm portion 16 on the driven shaft 9 side. As shown in fig. 6, a through hole 16b that opens toward the rotation axis storage hole 14b of the tilt table 14 is formed in the arm portion 16 on the driven shaft 9 side. Therefore, the rotation shaft accommodating hole 14b communicates with the gear train space 16a on the driven shaft 9 side via the through hole 16 b.

In addition, the end portion of the rotary drive shaft 44c on the other end side is positioned in the gear train space 16 a. Further, a through hole 16c that opens toward the through hole 9c of the driven shaft 9 is also formed in the arm portion 16 on the driven shaft 9 side. Therefore, the tip end portion of the output shaft 41a of the rotation drive motor 41 protruding from the driven shaft 9 as described above is also positioned in the gear train space 16 a.

A drive gear 45a is fixed to the output shaft 41a of the rotation drive motor 41 and a portion located in the gear train space 16 a. A driven gear 45c is fixed to the rotation driving shaft 44c and a portion located in the gear train space 16 a. The driven gear 45c and the drive gear 45a are coupled to each other via one or more transmission gears 45b in the gear train space 16 a. The rotation of the output shaft 41a of the rotation driving motor 41 is transmitted to the worm gear mechanism 44 through a gear train 45 including the driving gear 45a, the transmission gear 45b, and the driven gear 45 c.

In this way, the rotation driving unit 4 is configured to transmit the rotation of the output shaft 41a of the rotation driving motor 41 as a driving source to the support shaft 17 by the drive transmission mechanism 43 including the gear train 45 and the worm gear mechanism 44, and to rotate and drive the support shaft 17. Thereby, the rotary drive unit 4 rotationally drives the rotary table 7 supported by the support shaft 17.

In the rotation driving unit 4, a third reservoir 33 and a fourth reservoir 34 are provided in a space inside the tilt frame 6, corresponding to the respective gear mechanisms, for storing lubricating oil for lubricating the corresponding gear mechanisms.

The storage portion 33 corresponding to the worm gear mechanism 44 is provided in a space (hereinafter, also referred to as "inclined table side space") 14c formed by the support shaft receiving hole 14a and the rotation shaft receiving hole 14 b.

More specifically, as shown in fig. 4, an oil seal 51 is provided in the support shaft accommodating hole 14a on the side from which the support shaft 17 protrudes, so as to be interposed between the inner peripheral surface of the support shaft accommodating hole 14a and the outer peripheral surface of the support shaft 17. Further, an oil seal 52 is provided in the support shaft accommodating hole 14a on the side where the back cover 19 is provided so as to be interposed between the inner peripheral surface of the through hole 19a in the back cover 19 and the outer peripheral surface of the support shaft 17. Therefore, the support shaft accommodating hole 14a is in a state in which portions communicating with the outside of the tilt table 14 on both sides in the direction of the axis L2 of the support shaft 17 are sealed.

As shown in fig. 6, the portion of the rotation shaft housing hole 14b that opens to the tilt drive shaft 8 side as described above is closed by the tilt drive shaft side arm portion 15. Further, an O-ring seal 53 is interposed between the periphery of the opening of the rotation shaft receiving hole 14b in the side surface on the tilt drive shaft 8 side and the arm portion 15 on the tilt drive shaft side. Thus, the inclined table side space 14c formed by the support shaft receiving hole 14a and the rotation shaft receiving hole 14b is in a state where each portion communicating with the outside is sealed.

In addition, a third seal member 54 serving as an oil seal 54 is provided in the rotating shaft receiving hole 14b of the inclined table side space 14c at a position closer to the driven shaft 9 than the worm 44b of the rotating drive shaft 44c so as to be interposed between the inner peripheral surface of the rotating shaft receiving hole 14b and the outer peripheral surface of the rotating drive shaft 44 c. However, the third seal member 54 is provided on the driven shaft 9 side of the bearing B7 with respect to the bearing B7 on the driven shaft 9 side of the two bearings supporting the above-described rotary drive shaft 44 c. Thus, the tilt table side space 14c is separated from the space in the rotating shaft receiving hole 14b on the driven shaft 9 side of the third seal member 54 at the portion closer to the tilt driving shaft 8 side than the third seal member 54.

In the inclined table side space 14c, a portion on the inclined drive shaft 8 side stores lubricating oil for lubricating the worm gear mechanism 44. Therefore, the portion on the tilt drive shaft 8 side becomes the storage section (third storage section) 33 corresponding to the worm gear mechanism 44.

The reservoir 34 corresponding to the gear train 45 that connects the output shaft 41a of the rotation drive motor 41 and the rotation drive shaft 44c is provided in the gear train space 16a of the arm portion 16 on the driven shaft 9 side.

More specifically, an oil seal 55 is provided in a through hole 9c of the driven shaft 9, which penetrates the output shaft 41a of the rotation drive motor 41, so as to be interposed between the inner peripheral surface of the through hole 9c and the outer peripheral surface of the output shaft 41 a. Therefore, the gear train space 16a in the arm portion 16 on the driven shaft 9 side is sealed at a portion communicating with the outside on the driven shaft 9 side. An O-ring seal 56 is interposed between the periphery of the opening of the through hole 9c in the end surface on the one end side of the driven shaft 9 and the arm portion 16 on the driven shaft 9 side.

A fourth seal member 57 serving as an oil seal 57 is provided in the through hole 16b of the arm portion 16 on the driven shaft 9 side, which is open toward the rotation shaft receiving hole 14b, so as to be interposed between the inner peripheral surface of the through hole 16b and the outer peripheral surface of the rotation driving shaft 44 c. The gear train space 16a is separated from the space (the inclined table side space 14c) in the rotating shaft receiving hole 14b by the fourth seal member 57. In addition, lubricating oil for lubricating the gear train 45 is stored in the gear train space 16 a. Therefore, the gear train space 16a serves as a storage section (fourth storage section) 34 corresponding to the gear train 45.

In the machine tool 1 configured as described above, in the present invention, the rotary indexing device 2 of the machine tool 1 is a detection device for detecting a height position of an oil surface of the lubricating oil stored in the reservoirs 31 to 34 (hereinafter, also simply referred to as "height position"), and includes a detection device provided in one-to-one correspondence with a detection target reservoir set as a detection target in the reservoirs 31 to 34.

Moreover, the present embodiment is an example as follows: in the inclined circular table 2 as the rotary indexing device 2, all of the four storage units 31 to 34 are set as detection target storage units, and four detection devices 61 to 64 are provided. In the present embodiment, the inclined circular table 2 includes display devices 71 to 74 for displaying information on the height positions detected by the detection devices 61 to 64. The details of the characteristic parts of the machine tool 1 including such a rotary indexing device 2 are as follows.

As described above, the inclined circular table 2 includes the first to fourth reservoirs 31 to 34. The detecting devices 61 to 64 are provided in a one-to-one correspondence with the storage sections 31 to 34. First, the detection devices 61 to 64 corresponding to the first storage unit 31 (hereinafter also referred to as "first detection device") 61 and the configurations related thereto will be described.

First, as shown in fig. 3, in the drive support base 5B of the tilt drive section 3, the worm shaft accommodating hole 22B in the first storage section 31 has a portion (hereinafter also referred to as "large diameter portion") 22c formed so as to expand the inner diameter of the hole 22B at a position above the upper bearing B4 and the upper bearing B4 among the bearings B5 that support the upper and lower portions of the worm shaft 26 c.

In addition, the frame main body 22 of the drive support base 5b of the tilt drive unit 3 is formed with a first frame-side communication passage 22e and a second frame-side communication passage 22f, which are two communication passages (hereinafter also referred to as "frame-side communication passages") that communicate with the large diameter portion 22c of the worm shaft storage hole 22b and that open to the side surface (outer side surface) 22d facing the opposite side of the tilt frame, of the two side surfaces of the frame main body 22 in the thickness direction, so as to be displaced in the vertical direction of the frame main body 22.

Of the two frame-side communication paths, the first frame-side communication path 22e, which is the upper frame-side communication path, is formed so as to communicate with the large diameter portion 22c at a position near the upper end of the large diameter portion 22 c. On the other hand, the lower second frame-side communication passage 22f is formed so as to communicate with the large diameter portion 22c at a position near the lower end of the large diameter portion 22 c. Each of the frame-side communication passages is formed so as to open on the outer side surface 22d and at a position opposite to the worm shaft 26c side with respect to the tilt drive shaft 8. Therefore, each frame-side communication passage is formed so that a portion communicating with the large diameter portion 22c in the front-rear direction extends beyond the tilt drive shaft 8, and is bent at a position opposite to the worm shaft 26c side with respect to the tilt drive shaft 8, so as to open to the outer side surface 22 d.

In addition, as shown in fig. 3 and 4, the first detection device 61 is provided in the form of an outer side surface 22d attached to the frame main body portion 22 of the tilt driving portion 3. The first detecting device 61 is composed of a main body seat 61a attached to the frame main body portion 22 of the tilt driving unit 3 and a detector 61h attached to the main body seat 61 a.

The main body seat 61a is a substantially rectangular parallelepiped member formed so that four side surfaces thereof are rectangular and an upper surface and a lower surface thereof are substantially square. The main body mount 61a is attached to the drive support base 5b of the tilt drive unit 3 on one of the four side surfaces. Therefore, the side surface serves as the mounting surface 61 b. The main body base 61a is provided with a hole 61c (hereinafter also referred to as a "detection hole") in which a detector 61h described below is provided, and the hole 61c is a bottomed hole that is open on the upper surface and closed on the lower surface side.

Further, two communication passages (hereinafter also referred to as "detector-side communication passages") that communicate with the detection hole 61c and open to the mounting surface 61b, i.e., a first detector-side communication passage 61d and a second detector-side communication passage 61e, are formed in the main body base 61a so as to be shifted in position in the depth direction of the detection hole 61 c. Further, of the two detector-side communication passages, the upper first detector-side communication passage 61d and the lower second detector-side communication passage 61e are formed so that the interval therebetween coincides with the interval in the vertical direction between the first frame-side communication passage 22e and the second frame-side communication passage 22 f.

In addition, the detector 61h is mounted on the upper surface of the main body base 61 a. In the present embodiment, the detector 61h is a so-called guided pulse type liquid level sensor that detects the position of a detection target (the oil surface) by microwaves. Specifically, the detector 61h includes a detector main body 61i attached to the upper surface of the main body holder 61a, and a rod-shaped detection rod 61j provided to protrude from the detector main body 61 i.

The detector 61h calculates the distance to the detection object based on the time until the microwave transmitted from the detector main body 61i toward the detection object is reflected by the detection object (the oil surface) and received by the detector main body 61 i. The detection rod 61j is used to assist transmission and reception of microwaves in the detector main body 61 i. The detector 61h is attached to the upper surface of the main body holder 61a in the detector main body 61i so that the detection rod 61j is positioned in the detection hole 61c of the main body holder 61 a.

In addition, the first detection device 61 is attached to the outer side surface 22d of the frame body 22 in the drive support base 5b of the tilt drive unit 3 on the attachment surface 61b in such a configuration that the first detector-side communication passage 61d communicates with the first frame-side communication passage 22e and the second detector-side communication passage 61e communicates with the second frame-side communication passage 22 f. Thus, the detection hole 61c of the first detection device 61 is in a state of being communicated with the first reservoir 31 via each detector-side communication passage and each frame-side communication passage. Further, an O-ring seal 61p is interposed between the periphery of the opening of the first detector-side communication passage 61d in the attachment surface 61b of the main body seat 61a and the outer side surface 22d of the frame main body 22. An O-ring seal 61q is also interposed between the periphery of the opening of the second detector-side communication passage 61e in the mounting surface 61b of the main body seat 61a and the outer side surface 22d of the frame main body 22.

As a result, in a state where the oil surface of the lubricating oil stored in the first reservoir 31 for lubricating the worm gear mechanism 44 is present between the first frame-side communication passage 22e and the second frame-side communication passage 22f in the large diameter portion 22c in the vertical direction, the lubricating oil flows into the detection hole 61c through the second frame-side communication passage 22f and the second detector-side communication passage 61e, and the height position in the detection hole 61c is matched with the height position in the first reservoir 31.

In the present embodiment, the lubricating oil stored in the first reservoir 31 is also subject to lubrication by the bearings B4 and B5 that support the upper and lower worm shafts 26 c. Therefore, the height position in the first reservoir 31 needs to be at least higher than the upper bearing B4. The lower limit of the height position is defined as a position slightly above the upper bearing B4.

In addition, in the first reservoir 31, the large diameter portion 22c is formed directly above the upper bearing B4, and the lower second frame-side communication passage 22f of the two frame-side communication passages is formed so as to communicate with the large diameter portion 22c at a position close to the lower side of the large diameter portion 22 c. Thus, even in a state where the height position in the first storage section 31 is at the lower limit, the height position in the detection hole 61c matches the height position in the first storage section 31. Therefore, the state in which the height position in the first storage unit 31 is at the lower limit can also be detected by the first detection device 61.

In addition, as for the upper limit of the height position, the temperature of the lubricating oil rises during operation in the inclined circular table 2, and the volume of the lubricating oil may expand with the rise in temperature. In this case, if the size of the space above the oil surface of the first reservoir 31 in the initial state before the inclined circular table 2 is operated is small enough to not allow the expansion, the pressure of the lubricating oil increases during the operation due to the expansion. Therefore, the height position in the initial state is preferably a position where a space having a size that allows at least the expansion during the operation is formed above the oil surface. Therefore, the height position in the initial state is set to a position where such a space is formed above the oil level.

In addition, the first frame-side communication path 22e on the upper side is formed to communicate with the large diameter portion 22c at a position near the upper end of the large diameter portion 22 c. That is, the first frame-side communication passage 22e is formed so that the detection hole 61c communicates with the space above the oil level formed in the first reservoir 31. As a result, air can move between the first reservoir 31 and the detection hole 61 c. Thus, even in a state where the height position in the first reservoir 31 is located near the upper end of the first reservoir 31, the height position in the detection hole 61c coincides with the height position in the first reservoir 31. Therefore, the state in which the height position of the first storage section 31 is located near the upper end of the first storage section 31 can also be detected by the first detection device 61.

Next, a detection device (hereinafter also referred to as "second detection device") 62 corresponding to the second storage unit 32 and a configuration related thereto will be described. The second detection device 62 itself has substantially the same configuration as the first detection device 61 described above.

First, as shown in fig. 2 and 3, the second storage section 32 includes the internal space 23a of the motor mounting section 23 in the drive support base 5b of the tilt drive section 3, as described above. In addition, an upper through hole 22i and a lower through hole 22j, which are two through holes, are formed in the motor mounting portion 23 in a vertically aligned manner in a side wall 22h including a side surface (outer side surface 23d) facing the same side as the outer side surface 22d of the frame main body portion 22 to which the first detection device 61 is mounted. Therefore, the internal space 23a of the motor mounting portion 23 communicates with the outside through the two through holes corresponding to the frame-side communication passage in the configuration related to the first detection device 61 described above.

Of the two through holes, the upper through hole 22i is formed to be open in the internal space 23a at a position near the upper end of the internal space 23 a. On the other hand, the lower through hole 22j is formed to open into the internal space 23a at a position lower than the gear train 27 in the motor mounting portion 23.

In addition, the second detection device 62 is attached to the outer side surface 23d of the motor mounting portion 23. However, in the second detection device 62, the interval between the two detector-side communication passages (the upper first detector-side communication passage 62d and the lower second detector-side communication passage 62e) in the main body seat 62a matches the interval between the upper through hole 22i and the lower through hole 22j in the motor mounting portion 23.

The second detection device 62 is attached to the outer side surface 23d of the motor mounting portion 23 on the attachment surface 62b in such a manner that the first detector-side communication passage 62d communicates with the upper through hole 22i of the motor mounting portion 23 and the second detector-side communication passage 62e communicates with the lower through hole 22 j. Thus, the detection hole 62c of the second detection device 62 is in a state of being communicated with the second reservoir 32 via each detector-side communication passage and each through hole.

Further, the lubricating oil stored in the second reservoir 32 is set to a position above the oil surface in a space of a size that allows at least the expansion during the operation, as in the height position in the first reservoir 31. The upper through hole 22i is provided at a position near the upper end of the internal space 23a as described above, and the height position in the detection hole 62c can be detected by the second detection device 62 by matching the height position with the height position in the internal space 23 a.

The height position needs to be located above the lower surface of the gear train 27 to be lubricated. Therefore, the lower through hole 22j is located below the gear train 27 as described above. That is, the second detection device 62 is provided so as to be able to detect the height position up to a position lower than the gear train 27. However, the lower limit of the height position of the lubricating oil in the second reservoir 32 is set to a position slightly above the lower surfaces of the drive gear 27a, the transmission gear 27b, and the driven gear 27c, which are all the gears included in the gear train 27. An O-ring seal 62p is interposed between the periphery of the opening of the first detector-side communication passage 62d in the attachment surface 62b of the main body seat 62a and the outer side surface 23d of the motor attachment portion 23. An O-ring seal 62q is also interposed between the periphery of the opening of the second detector-side communication passage 62e in the mounting surface 62b of the main body seat 62a and the outer side surface 23d of the motor mounting portion 23.

Next, as shown in fig. 6, a detection device (hereinafter, also referred to as a "third detection device") 63 corresponding to the third storage unit 33 and a configuration related thereto will be described.

First, in the tilt table 14 described above, the portion of the third reservoir 33 that houses the worm 44b is formed as a large diameter portion 14d having a larger inner diameter (hereinafter also referred to as "large diameter portion for worm") than the other portions, in the housing hole 14b for the rotation shaft. In addition, as shown in fig. 2, two through holes, i.e., an upper through hole 14h and a lower through hole 14i, are formed in the tilt table 14 and in a front wall 14f including a front side surface 14e of the tilt table 14 so as to be aligned in the plate thickness direction.

As shown in fig. 6, an upper through hole 14h of the two through holes is formed so as to open at the worm large diameter portion 14d at a position close to the upper surface side (upper end) of the tilt table 14 in the plate thickness direction of the worm large diameter portion 14 d. On the other hand, the lower through hole 14i is formed in the large diameter portion 14d for the worm so as to open at a position close to the lower surface side (lower end) of the inclined table 14 in the plate thickness direction of the large diameter portion 14d for the worm.

In addition, the third detecting device 63 is provided so as to be attached to the front side surface 14e of the tilt table 14. In the third detecting device 63, the main body holder 63a is formed to have a rectangular shape in the upper and lower surfaces thereof with respect to the main body holder 61a of the first detecting device 61 and the main body holder 62a of the second detecting device 62. However, the upper surface and the lower surface of the rectangle are formed as surfaces whose dimensions in the longitudinal direction are sufficiently larger than those in the short direction. Therefore, two of the four side surfaces are also formed to have a dimension in the longitudinal direction sufficiently larger than a dimension in the short direction (hereinafter, also referred to as "laterally long side surfaces"). The third detecting device 63 is attached to the tilt table 14 on one of the lateral long side surfaces, which serves as the attachment surface 63 b.

As shown in fig. 2, the main body seat 63a has a detection hole 63c opened in the upper surface thereof at a position close to one end side in the longitudinal direction. In the main body base 63a, two detector-

side communication passages

63d and 63e communicating with the detection hole 63c are formed so as to open on the mounting surface 63b at a position close to the other end side in the longitudinal direction. The distance between the openings of the two detector-side communication passages in the main body mount 63a, i.e., the upper first detector-side communication passage 63d and the lower second detector-side communication passage 63e, on the mounting surface 63b is equal to the distance between the two through holes in the tilt table 14.

In addition, the third detection device 63 is attached to the front surface 14e of the tilt table 14 on the attachment surface 63b in such a manner that the first detector-side communication passage 63d communicates with the upper through hole 14h of the tilt table 14 and the second detector-side communication passage 61e communicates with the lower through hole 14 i. Therefore, the two through holes in the tilt table 14 correspond to the frame-side communication path in the configuration related to the first detection device 61 described above. As shown in fig. 6, an O-ring seal 63p is interposed between the periphery of the opening of the first detector-side communication passage 63d in the attachment surface 63b of the main body mount 63a and the front side surface 14e of the tilt table 14. An O-ring seal is also interposed between the periphery of the opening of the second detector-side communication passage 63e in the mounting surface 63b of the main body mount 63a and the front side surface 14e of the tilt table 14.

In a state where the upper surface of the rotary table 7 is in the inclined circular table 2 in a direction parallel to the horizontal direction (hereinafter, also simply referred to as "horizontal state"), the lubricating oil stored in the third reservoir 33 needs to be located above the meshing position in the worm gear mechanism 44 (worm 44b, worm wheel 44a) to be lubricated. Therefore, the lower through hole 14i is provided in the position near the lower end of the large diameter portion 14d for worm. However, the lower limit of the height position of the lubricating oil in the third reservoir 33 is defined as a position slightly above the meshing position.

As described above, the third reservoir 33 includes the support shaft receiving hole 14a, and the support shaft receiving hole 14a has a portion located above the worm large diameter portion 14d in the horizontal state. Therefore, even if the large diameter portion 14d for the worm is filled with the lubricating oil, the third reservoir 33 allows expansion of the lubricating oil during operation of the inclined circular table 2 by the receiving hole 14a for the support shaft.

However, if the large diameter portion 14d for the worm is filled with the lubricating oil, in the configuration in which the through hole (the frame-side communication passage) is formed at the above-described position, air is in a state in which it is not possible to move between the reservoir portion (the large diameter portion 14d for the worm) 33 and the detection hole 63 c. Therefore, the upper limit of the height position of the third reservoir 33 is defined to be slightly lower than the upper through-hole (frame-side communication passage) 14h in the horizontal state. By defining the upper limit of the height position with respect to the upper through hole 14h in this manner, the height position of the third reservoir 33 can be detected by the third detection device 63.

Next, a detection device (hereinafter also referred to as "fourth detection device") 64 corresponding to the fourth reservoir 34 and a configuration related thereto will be described. The fourth detection device 64 itself has substantially the same configuration as the first detection device 61 described above.

First, the fourth reservoir 34 includes the space 16a for the gear train in the arm portion 16 on the driven shaft 9 side as described above. In addition, as shown in fig. 2, two through holes, i.e., an upper through hole 16h and a lower through hole 16i, are formed in a vertically aligned manner in the arm portion 16 on the driven shaft 9 side of the rotary drive unit 4 on a front wall 16e including a surface facing the same side as the front side surface 14e of the tilt table 14 (a front side surface 16d in the arm portion 16 on the driven shaft 9 side). Therefore, the gear train space 16a of the arm portion 16 on the driven shaft 9 side communicates with the outside through the through holes, and the two through holes correspond to the frame-side communication path in the configuration related to the first detection device 61 described above.

Further, a lower through hole 16i of the two through holes is formed through the front wall 16e at a position lower than the transmission gear 45b in the gear train space 16a in the horizontal state. In addition, as shown in fig. 2 and 6, the upper through hole 16h is formed through the front wall 16e at a position where the distance between the lower through hole 16i and the distance between the two detector-side communication passages in the main body seat 64a of the fourth detection device 64 coincide with each other.

The fourth detection device 64 is attached to the front surface 16d of the arm portion 16 on the driven shaft 9 side on the attachment surface 64b, with an arrangement in which the first detector-side communication passage 64d communicates with the upper through hole 16h of the arm portion 16 on the driven shaft 9 side, and the second detector-side communication passage 64e communicates with the lower through hole 16 i. Thus, the detection hole 64c of the fourth detection device 64 is in a state of being communicated with the fourth reservoir 34 via each detector-side communication passage and each through hole. Further, an O-ring seal 64p is interposed between the periphery of the opening of the first detector-side communication passage 64d in the attachment surface 64b of the main body seat 64a and the front side surface 16d of the arm portion 16 on the driven shaft 9 side. An O-ring seal is also interposed between the periphery of the opening of the second detector-side communication passage 64e in the mounting surface 64b of the main body seat 64a and the front side surface 16d of the arm portion 16 on the driven shaft 9 side.

Further, with respect to the lubricating oil stored in the fourth reservoir 34, the drive gear 45a which is the uppermost side in the horizontal state in the gear train 45 to be lubricated is lubricated by the transmission gear 45b meshing with the drive gear 45a, and is indirectly lubricated. Therefore, the above-mentioned height position needs to be at least the position where the transmission gear 45b is lubricated by the lubricating oil. Therefore, the lower limit of the height position is defined to be slightly above the meshing position of the transmission gear 45b and the driven gear 45c in the horizontal state.

As described above, the fourth storage unit 34 includes the gear train space 16a, and the gear train space 16a is a space in which a large space is present above the gear train 45 (the drive gear 45 a). Therefore, even if the gear train space 16a is filled with the lubricating oil so as to immerse the gear train 45, the fourth reservoir 34 can allow expansion of the lubricating oil during the operation of the tilt circular table 2.

However, as with the other detecting devices 61 to 63, it is necessary to have a state in which air can move between the gear train space 16a and the detecting hole 64 c. Therefore, the upper limit of the height position of the fourth reservoir 34 is defined to be slightly lower than the upper through hole (frame-side communication passage) 16h in the horizontal state, similarly to the third reservoir 33. By defining the upper limit of the height position with respect to the upper through hole 16h in this manner, the height position of the fourth reservoir 34 can be detected by the fourth detection device 64.

Further, as shown in FIG. 2, in the present embodiment, the inclined circular table 2 includes display devices 71 to 74 connected to the detection devices 61 to 64 and displaying information on the height positions detected by the detection devices 61 to 64. In the present embodiment, the display devices 71 to 74 are provided in one-to-one correspondence with the respective detection devices. Therefore, the inclined circular table 2 of the present embodiment is provided with four display devices 71 to 74. However, in the present embodiment, the display devices 71 to 74 are provided integrally with the detectors 61h to 64h of the corresponding detection devices 61 to 64 so as to be attached to the upper portions of the detector main bodies 61i to 64i of the detectors 61h to 64 h. The display devices 71 to 74 themselves are the same in structure as the detection devices 61 to 64.

The information on the height positions displayed by the display devices 71 to 74 is the detection results (the distances from the detector main bodies 61i to 64i to the oil surface) of the detectors 61h to 64h in the respective detection devices 61 to 64. The display devices 71 to 74 are configured to display the detection results in a digital form. Therefore, each of the display devices 71 to 74 includes display sections 71a to 74a for displaying the number based on the detection result in the corresponding detection device 61 to 64.

As described above, the display devices 71 to 74 are provided integrally with the detectors 61h to 64h and are provided inside the exterior cover 1f of the machine tool 1. Therefore, the display devices 71 to 74 are provided in such a direction that the worker can view the display portions 71a to 74a from the outside of the exterior cover 1f in the initial state and the horizontal state.

According to the machine tool 1 including the inclined circular table 2 described above, the height positions of the lubricating oil stored in the respective reservoirs 31 to 34 are detected by the detection devices 61 to 64 provided in one-to-one correspondence with the respective reservoirs 31 to 34 with respect to the first reservoir 31 to the fourth reservoir 34 as the reservoir to be detected. The detection results of the detection devices 61 to 64 are displayed on display units 71a to 74a of display devices 71 to 74 provided integrally with the detectors 61h to 64h of the detection devices 61 to 64. Therefore, the worker can confirm the detection result by visually observing the display portions 71a to 74a (display contents).

As described above, the detection result is the distance from the detectors 61h to 64h (detector main bodies 61i to 64i) to the oil surface. However, since the relationship between the height position (oil amount) of the oil level and the distance in each of the reservoirs 31 to 34 is unique, the worker can grasp the height position by checking the distance. Further, although the upper and lower limits of the height position are defined as described above for each of the storage sections 31 to 34, the state of the height position with respect to the upper and lower limits can be grasped. For example, in each of the storage units 31 to 34, the upper limit and the lower limit of the height position are converted into the distance in advance, and the worker can confirm the value in advance, so that the upper limit and the lower limit can be compared with the detection result more easily.

Further, by providing the display devices 71 to 74 in advance such that the display portions 71a to 74a can be visually observed from the outside of the exterior cover 1f in the machine tool 1 as described above, for example, the state of the height position in the storage portions 31 to 34 can be easily confirmed from the outside of the exterior cover 1f before the start of operation of the machine tool 1 in which the inclined circular table 2 is in the initial state (the horizontal state). Therefore, according to the machine tool 1, the operator can easily grasp the state of the height position of each of the storage units 31 to 34, as compared with the conventional machine tool 1 including the rotary indexing device that manages the amount of oil using an oil gauge.

The present invention is not limited to the embodiment (the above-described example) described above, and can be implemented in another embodiment (a modification) described below.

(1) In the above embodiment, the rotary indexing device included in the machine tool according to the present invention employs the tilt circular table 2 including the tilt side driving unit 3 and the rotary driving unit 4, which are two types of rotary indexing devices including the tilt driving unit 3 and the rotary driving unit 4. However, the rotary indexing device of the present invention is not limited to such a tilting circular table, and may be a tilting table device constituted only by a rotary indexing device corresponding to the tilt driving unit 3 of the above-described embodiment, or a circular table constituted only by a rotary indexing device corresponding to the rotary driving unit of the above-described embodiment.

The circular table may be a so-called vertical circular table configured to index the angular position of the target member around the horizontal axis, or a so-called horizontal circular table configured to index the angular position of the target member around the vertical axis.

In the above-described embodiment, each rotary indexing device is configured such that the rotary shaft (the tilt drive shaft 8 and the support shaft 17) to which the member to be rotated is attached is coupled to the drive motor via two gear mechanisms, i.e., a worm gear mechanism and a gear train. As a result, two storage units are provided for each rotary indexing device. However, in the present invention, the rotary indexing device may be configured such that the rotary shaft is coupled to the drive motor by a single gear mechanism such as a worm gear mechanism. In this case, the rotary indexing device includes one storage portion.

(2) In the embodiment described above, the four storage units 31 to 34 are included in the rotary index device, and all of the four storage units 31 to 34 are set as the detection target storage units. That is, all the storage sections 31 to 34 included in the rotary indexing device are set as detection target storage sections. However, even when the rotary indexing device includes a plurality of storage units, the present invention is not limited to the storage units to be detected as a whole, and only a part of the storage units may be set as the storage units to be detected.

(3) As for the detection means, in the above-described embodiment, the detection means employs guide pulse type liquid level sensors as the detectors 61h to 64 h. However, in the present invention, the detection device may employ, for example, an ultrasonic level sensor or a laser level sensor as the detector.

In addition, the present invention is not limited to the use of such a detector that can linearly detect the position of the detection target (the oil level), and a detector (e.g., an optical level sensor or a float level sensor) that can detect when the detection target (the oil level) reaches (exceeds) a predetermined detection position may be used.

In such a detector, although the height position cannot be detected as in the detector of the above-described embodiment and the like, for example, by setting the lower limit of the height position to the detection position, it is possible to grasp that the height position which is a problem in lubricating the gear mechanism is lower than the lower limit, and therefore, in this respect, the amount of oil can be managed. Therefore, in the aspect of the management of the amount of oil according to the object of the present invention, the detector can be applied to the detection device of this type. The detection device of the present invention detects the height position, and the detection of the height position also includes a state of detecting the height position.

(4) As for the display device, the above-mentioned embodiment is an example of providing the display devices 71 to 74 which display the information related to the height positions detected by the detection devices 61 to 64. In addition, the display devices 71-74 are provided integrally with the detectors 61 h-64 h of the corresponding detection devices 61-64. However, even when the machine tool includes the display device as described above, the display device is not limited to being provided integrally with the detector in the present invention. For example, the display device may be provided outside the exterior cover 1f of the machine tool 1 so as to be attached to the outer surface of the peripheral wall 1h of the exterior cover 1 f. The display device is not limited to displaying the detection result of the detection device in a numerical manner as in the above-described embodiment, and may display a message based on the detection result in a text manner or may light up a warning lamp according to the detection result.

However, the present invention does not necessarily require the provision of such a display device, and the machine tool of the present invention may not include a display device. For example, an alarm for emitting a warning sound based on the detection result of the detection device may be provided instead of the display device. Further, the information on the height position detected by the detection device may be output to a control device of the machine tool and used by the control device of the machine tool. The method of using the control device is, for example, a method of not operating the machine tool when information corresponding to the case where the height position is lower than the lower limit is input to the control device.

(5) The above-described embodiment is an example of the present invention applied to a machine tool 1 (so-called horizontal machining center) in which the direction of the rotation axis of the spindle 1a is the horizontal direction. However, the machine tool to which the present invention is applied is not limited to a horizontal machining center, and may be, for example, a machine tool in which the direction of the rotation axis of the spindle is a vertical direction (so-called vertical machining center).

The present invention is not limited to any of the embodiments described above, and can be modified as appropriate within the scope not departing from the gist of the present invention.

Claims

1. A machine tool including a rotary indexing device for indexing an angular position of a member to be rotated attached to an end portion of a rotary shaft, the rotary indexing device including a frame that houses the rotary shaft in a rotatably supported state, a drive motor that rotatably drives the rotary shaft, and a drive transmission mechanism that is housed in a space inside the frame and transmits rotation of an output shaft of the drive motor to the rotary shaft, the drive transmission mechanism including a gear mechanism, the space including one or more storage portions that store lubricating oil that lubricates at least the gear mechanism, the machine tool being characterized in that the drive transmission mechanism includes a gear mechanism,

2. The machine tool including a rotary indexing device according to claim 1,

a display device connected to the detection device and displaying information related to the height position detected by the detection device.

3. The machine tool including a rotary indexing device according to claim 2,